The Irish Postmasters' Union has got the backing of the Archbishop of Cashel in its campaign to end post office closures.
The IPU has called for the introduction of a public service obligation for post offices in more sparsely populated areas, to support the less commercially successful offices.
"While we recognise that not all rural post offices are viable as we have become a more urbanised society, there needs to be a policy in terms of what the minimum geographic service area should be. Post offices providing this service, whose income falls below an agreed threshold, should be supported through a PSO approach," said general secretary John Kane.
The Archbishop of Cashel, Dermot Clifford, told the annual conference of the Irish Postmasters' Union in Mullingar he backed their call on the government to recognise the social value of the Post Office network by introducing a PSO for some rural offices.
"The local Post Office is a vital link between the citizen and the State and in many places it is the only link left," he said
"Every citizen is entitled to have the services of the Post Office available to him or her at a reasonable distance — and a clear national policy on this is urgently needed."
Some 500 post offices have been closed in the past eight years, and there are now 1,200 remaining throughout the country.
Mr Kane warned that the lack of Government policy in relation to network size and coverage means that closures are taking place on an "ad hoc" basis, and would result in an increasingly uneven spread of Post Office services, with more sparsely populated areas at risk of becoming poorly serviced.